Let’s keep it simple: dataLayer is like a suitcase where your website packs all the important stuff — user actions, events, and other juicy data — before sending it off to Google Tag Manager or other tools. But here’s the kicker: dataLayer isn’t just about data. It’s a multitasking genius. Here are five things about it that might surprise you (or even make you smile):
1. dataLayer isn’t just a list — it’s a data wizard
Sure, it looks like a plain old array, but dataLayer can update itself dynamically using something called push. That means you can toss new data in there anytime, like mid-flight during a user’s session.
Example: Add the cart’s total value to dataLayer the moment someone adds an item, not just at checkout.
2. It’s got a memory like an elephant
If you shove data into dataLayer before a trigger fires, don’t worry — it won’t get lost. GTM will scoop it up later. So even if things don’t happen in perfect sync, your data stays safe and sound.
Think of a user clicking a button, the data going into dataLayer, and the trigger firing a second later. The info will still be right where you left it.
3. It’s not picky about what you throw in
Strings, numbers, objects, arrays — dataLayer can handle it all. That makes it a super versatile tool for even the trickiest analytics setups.
You can pass the entire cart contents — item IDs, prices, categories — all in one neat little package.
4. It’s not just for GTM
While dataLayer is best buddies with GoogleTagManager, it’s not exclusive. Other tools can also tap into its powers. Think of it as a data-sharing hub that plays nice with everyone.
Some ad platforms can directly read dataLayer events, no GTM required. Sharing is caring!
5. Events are its secret sauce
dataLayer isn’t just about stashing data — it also handles events like a pro. These events can trigger tags in GTM, giving you pinpoint control over what happens and when.
For instance, you can fire a purchase event with order details and trigger conversion tags only under specific conditions.
If you work with GA4 to BigQuery exports, be sure to check out my SQL cheat sheet.
